This invention relates to an electrical connector and, in particular, to a connector suitable for transmission of a high-frequency signal used in a communication apparatus or the like.
Recently, a DVI (Digital Visual Interface) is known as one of standards for an interface connecting a computer and a display. In the DVI, a serial transmission method called TMDS (Transition Minimized Differential Signaling) is used. According to the DVI, a digital signal can directly be sent from the computer to a digital display, i.e., a digitally-driven display. It is therefore possible to reduce signal degradation as a result of conversion from the digital signal into an analog signal. An electrical connector in conformity with the DVI will hereinafter be called a DVI connector.
In the DVI connector also, EMI protection is required as in a connector disclosed, for example, in Japanese Patent Application Publication (JP-A) 2002-270307 (corresponding to U.S. Pat. No. 6,547,595). The connector illustrated in JP-A 2002-270307 comprises a plurality of conductive contacts and a housing holding the contacts. The contacts are generally classified into a plurality of signal contacts and a plurality of shield contact for electromagnetically shielding the signal contacts. The shield contact has a shielding portion and serves to achieve impedance matching of the signal contacts and to thereby reduce insertion loss. In addition, one of the signal contacts farther from the shield contact is covered with the shielding portion so as to achieve impedance matching between the signal contacts.
Referring to FIG. 1, description will be made about a relationship between the signal contacts and the shield contact in the connector with EMI protection. In FIG. 1, a shield contact 3 is disposed adjacent to two signal contacts 1 and 2. The shield contact 3 has a main body portion 4 and a shielding portion 5 extending from the main body portion 4. The shielding portion 5 covers the signal contacts 1 and 2.
However, the shielding portion 5 has a plurality of protruding ends 6 which are not electrically terminated but electrically opened. This may result in electrical reflection at these protruding ends 6 and occurrence of noise.